Abstract Ternary spinel nitrides are a new class of semiconductor materials with tunable bandgap in the visible range. In this work, we report a rational design of spinel-type nitride compounds with improved features as solar cell absorber materials by way of the in-gap-band (IGB) concept. For this purpose, a systematic screening on the effect of transition metal (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo) hyperdoping on the crystal and electronic structure properties of germanium (Ge) and tin (Sn) spinel nitrides (γ-(MmSnx-mGe1-x)3N4, x = 0.5, m = 0.042, 0.083) was carried out through accurate ab-initio methods. The analysis of the electronic structure reveals that M-hyperdoped ternary spinel nitrides with M = Cr, Co, Cu show an IGB with the adequate properties to allow two extra photon absorption processes. A detailed study of the sunlight absorption properties, and maximum photovoltaic efficiencies reveal that Co-hyperdoped spinel is an excellent candidate to be used in photovoltaic devices as absorber material, with maximum photovoltaic efficiency of ~ 55%. Overall, our results suggest that it would be possible to design new ternary spinel-type nitride materials with improved absorption properties suitable for potential use in photovoltaic applications.

中文翻译：

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具有改进的太阳能电池吸收剂特性的尖晶石型氮化物化合物

摘要 三元尖晶石氮化物是一类在可见光范围内具有可调带隙的新型半导体材料。在这项工作中，我们通过带内（IGB）概念报告了一种具有改进特性的尖晶石型氮化物化合物作为太阳能电池吸收材料的合理设计。为此，系统筛选了过渡金属（M = Sc、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Nb、Mo）超掺杂对锗晶体和电子结构特性的影响(Ge) 和锡 (Sn) 尖晶石氮化物 (γ-(MmSnx-mGe1-x)3N4​​, x = 0.5, m = 0.042, 0.083) 通过精确的 ab-initio 方法进行。电子结构的分析表明，M = Cr、Co、Cu 的 M 超掺杂三元尖晶石氮化物显示出具有足够特性的 IGB，以允许两个额外的光子吸收过程。对太阳光吸收特性和最大光伏效率的详细研究表明，Co-超掺杂尖晶石是光伏器件中用作吸收材料的绝佳候选材料，最大光伏效率约为 55%。总体而言，我们的结果表明，有可能设计出具有改进的吸收特性的新型三元尖晶石型氮化物材料，适用于光伏应用的潜在用途。